Poly(etherimide ester)polymers comprised of the reaction products of (a) a low molecular weight diol, (b) a dicarboxylic acid, (c) a poly(oxy alkylene)diamine, and (d) a tricarboxylic acid or its derivatives are known and are described in U.S. Pat. Nos. 4,544,734 and 4,556,705 to McCready and in U.S. Pat. No. 4,556,688 to McCready et al. These poly(etherimide ester)polymers exhibit excellent stress-strain properties, low tensile set, high melting temperatures and/or excellent strength/toughness characteristics as well as good flexibility which are especially suitable for molding and extrusion applications.
It has now been discovered that poly(etherimide ester)polymers can be provided which exhibit lower flexural modulus and better flexibility than conventional presently available poly(etherimide ester)polymers. These poly(etherimide ester)polymers exhibiting these improved flexural properties are obtained by the utilization of a diol component which is comprised of a mixture of at least one low molecular weight diol and at least one high molecular weight diol.